Dragon Explorer of Osmoprotection Pathways (DEOP) is a unique web system focused on the exploration of manually-curated and in silico-curated information related to the production of osmoprotectants captured from 1,160 species and includes 834 pathways, 3,529 genes, 4,899 enzymes, 2,907 compounds (143 osmoprotectant compounds) and 4,052 reactions (1,889 reactions directly affecting an osmoprotectant). The system allows the user to test their genomic sequences in relation to osmoprotectant pathways.